Ever since being presented at the Paris Exposition of 1859, aluminum has been significant in the modern decorative arts.

For us it’s remained daring. Instead of embroidering our serveware to hide flaws, we create sleek designs and naked surfaces, the pure sheen on which any imperfection will show. We’ve learned that to realize designs in aluminum perfectly you must be able to carve a statue, build a sand castle, polish a gem. It also helps to have the instincts of a master chef.

Up in Massachusetts, our designer Michael Updike sculpts a new piece in clay, then casts it in dental plaster. He and Livia take it down to the most appropriate of our workshops in Mexico. There our artesanos hand-work an exact copy, from which a single metal mold is made.

This mold fits between two large boxes that get filled with a fine sand which holds a precise shape when pounded tight. Once sand envelops the design, the artisans lift off the top box and pull out the mold, leaving a perfect empty space.

Tubes are then pushed through the sand to make flow channels to the design cavity. One channel is for the molten aluminum; the others are to allow excess metal out. (On the underside of a Mariposa piece, you might spot the tiny mark of a channel.) When the boxes get joined tight again, the sand around the design cavity mustn’t budge even microscopically.

Once the molten aluminum reaches 1300 degrees, the artisans pour it down a flow channel until the cavity’s full. They stand on the box to keep it tight; the aluminum cools to a solid in 10 minutes. When they break open the box, sand spills all over.

The sand’s shoveled up and reused, someone fetches the mold, and the process starts again. Polishers go to work on the new piece with grinding and buffing wheels — and a washing machine they call la vibradora — to exact a perfect high gloss.

A team of eagle-eyed women make sure the men have gotten every detail right. Each piece takes over an hour, and gets made one at a time. If you want to push the limits of what can be shaped in aluminum, there’s simply no other way.